Kim Darroch.

A few days ago, the UK’s former spy chief warned his country is going through a political nervous breakdown. The leak of confidential memos by Britain’s ambassador to Washington about Donald Trump’s administration only seems to make that official.

Thanks to the disclosure of two years’ worth of cables by diplomat Kim Darroch, the US president now knows that however thick the British laid it on during his state visit to London last month, one of their most senior and respected diplomats views his administration as “uniquely dysfunctional” and “inept.” That’s awkward. It’s one thing to get an earful from your enemies. Even the thin-skinned Trump usually brushes those off with a clipped “fake news” dismissal. But it’s quite another to hear what your supposed friends say about you when they think you aren’t listening. Little wonder Trump sounded peeved when he said that Darroch “hasn’t served the UK well.”

The perpetrators of the leak haven’t been identified. The fallout will be an early challenge for Britain’s next prime minister, likely to be Boris Johnson. If Darroch is removed from his post before his scheduled retirement at the year-end, as Trump seems to want, it would only show just how reliant the country is on American goodwill as it prepares to leave the European Union and strike a new trade deal with the US. Should Johnson keep the diplomat in his posting, Trump might view it as a snub.

The cables may also make it harder to replace Darroch – a former permanent representative to the EU viewed with suspicion by Brexiters – with another diplomat unpopular with the same constituency: Mark Sedwill, the head of the civil service, who had been tipped as his successor.

The real problem with the leaks, though, isn’t so much their content or the diplomatic ripples they create. The ambassadorial role is important, but it’s not that important. The US-UK relationship is multi-layered, long-standing and complex. It can withstand a few indiscretions. The memos are shocking, rather, because they show the dysfunction and ineptitude at the heart of Britain’s own governing institutions.

The civil service is, above all, known for its independence, its professionalism and its dispassionate service to the government of the day. Staffers are inculcated to be apolitical, that rarest of qualities these days. They are paid to deliver their personal and professional assessments of the politics of their country of posting, just as Darroch did.

It’s almost impossible to see the leaking of a senior diplomat’s confidential correspondence as anything other than an act of national self-sabotage. Nigel Farage – the Brexit Party leader whom Trump once said would make a fine ambassador to the US – jumped on the leak to call for a purge of senior civil servants in favor of officials who were better disposed toward Trump and Brexit.

And this is where the leak suits the agenda of many Brexiters. They want to neutralize the civil service, to strike fear into the heart of any who dare to speak truth to power if those facts doesn’t serve their agenda. For them, any argument against Britain’s imminent exit from the EU, or against an economically damaging no-deal Brexit, is un-British. The warnings of skeptics – those who note that the Irish border isn’t the same as the Dover-Calais one, or that the EU has rejected the very path the Brexiters claim is clearly lit before them – are accused of breaking with the Dunkirk spirit that Brexit demands.

More than three years after the toxic Brexit campaign in which it was said that voters had had enough of experts, the leaking of the Darroch memos are a message to all experts that they remain unwelcome. That’s far more troubling than any hurt feelings in Washington caused by the ambassador’s candid comments.